[Red Moon]

I not so sure what would have happened. At the time of the Battle of Britain the British Army was a mess, even without air superiority he could have walked into Britain taken over the southern airfields with the army and taken control of the air. And in any case at the point the Germans gave up on attacking British Airfields in the Battle Britain they were actually winning and didn't even know it. A few weeks more of bombing our air bases and we were finished. Luck was on our side.....

But assuming we had fallen.... well the German army and it allies wouldn't have had there forces split between two fronts and the attack on Russia would have seen the Russian capital fall in 1942. You have to remember the Russian army was disorganized and out of date and it's air force lacked any modern aircraft types. It was only the slowing down of the German advance by being over stretched that stopped them.

Now say that most europe has fallen by 1944/45, would the Germans have stopped there?

Well it seems not. The German Rocket industry had plans to build the A9 and A10 missiles as a successor to the V2. Both of these missiles were true Inter-Continental Ballistic Missiles capable of reaching America, and work started on these in 1940 even before the USA joined the war in 1941. Other projects that shows the ambition of Germany is the Junkers 390, Messsermischimitte 264B and the Focke-Wulf Ta400, although these designs where started after the USA joined the war, they were all bombers capable of reaching the USA. In fact the a Junkers 390 approached within 12 miles of New York before turning back for home in a test flight in 1944.

The Germans technical advancement in Rocketry was amazing and without the help of the German scientists that created the V2 the USA would never have put man on the moon. Couple with this the British excellence in aircraft engine design, and the coupling together of the knowledge of jet engine design, there has to be a real possibility that the USA could fallen too.

In the end I think it would have come down to who could create the H bomb first, the USA or German Europe, but one things for sure if the German Europe had the Bomb first they would have had the means to deliver it much more effectively than the USA.

It is easy to forget, that by the time that the USA entered the war they were miles behind Europe in military aviation, and aircraft like the famous Mustang were designed to British specifications with a British engine. The USA reused a lot of British technology during the war and developed it further, but if Britain had fallen they wouldn't have had that technology in the first place.

In the end, we might have a nuclear winter, like No.1RachelFan! said, but I'm not sure it would be Europe's problem.